Re: pg_dump, ATTACH, and independently restorable child partitions

On Sat, Oct 24, 2020 at 02:59:49PM -0500, Justin Pryzby wrote:
> On Fri, Oct 23, 2020 at 12:29:40AM -0500, Justin Pryzby wrote:
> > Since this commit, pg_dump CREATEs tables and then ATTACHes them:
> >
> > |commit 33a53130a89447e171a8268ae0b221bb48af6468
> > |Author: Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
> > |Date: Mon Jun 10 18:56:23 2019 -0400
> > |
> > | Make pg_dump emit ATTACH PARTITION instead of PARTITION OF (reprise)
> > |...
> > | This change also has the advantage that the partition is restorable from
> > | the dump (as a standalone table) even if its parent table isn't
> > | restored.
> >
> > I like the idea of child tables being independently restorable, but it doesn't
> > seem to work.
> ...
> > Now that I look, it seems like this is calling PQexec(), which sends a single,
> > "simple" libpq message with:
> > |CREATE TABLE ..; ALTER TABLE .. ATTACH PARTITION;
> > ..which is transactional, so when the 2nd command fails, the CREATE is rolled back.
> > https://www.postgresql.org/docs/9.5/libpq-exec.html#LIBPQ-EXEC-MAIN
>
> The easy fix is to add an explicit begin/commit.

Now with updated test script.

--
Justin